Abstract: A printing system comprises one or more printheads arranged to eject ink to a deposition region. Print media are held by vacuum suction against a movable support surface, which transports the print media though the deposition region. The vacuum suction is communicated from a vacuum source to the movable support surface via a vacuum plenum. An airflow control system comprises one or more dampers arranged in the vacuum plenum to control airflow between the vacuum source and the movable support surface. The dampers have an adjustable impedance to airflow through the damper. The airflow control system is configured to adjust the impedance of the damper based on a detected condition of the printing system. A detected condition of the printing system may include, for example, a sensed pressure in the vacuum plenum.